Pneumatic starter pump for gas engines



June 19, 1934. w. o. BICKERSTAFF PNEUMATIC STARTER PUMP FOR GAS ENGINES Filed April 7, 1932 4 Sheets-Sheet l e 19, 1934- w. o. BICKERSTAFF 1,963,255

PNEUMATIC STARTER PUMP FOR GAS ENGINES Filed April 7, 1932 4 Sheets-Sheet 2 June 19, 1934. w. o. BICKERSTAFF 1,963,256

PNEUMATIC STARTER PUMP FOR GAS ENGINES Filed April 7. 1932 4 Sheets-Sheet 5' v %%%ZM w June 1934. w. o. BICKERSTAFF 1,963,256

PNEUMATIC STARTER PUMP FOR GAS ENGINES Filed April 7, 1932 4 Sheets-Sheet 4 Patented June 19, 1934 UNITED STATES PNEUMATIC STARTER PUMP FOR GAS ENGINES William Otho Bickers taff, Smithville, W. Va.

Application April '7, 1932, Serial No. 603,752

7 Claims.

This invention relates to starters for engines.

It is an object of this invention to start a gas engine through a medium of compressed gas. Further objects will be apparent from the specification and from the accompanying drawings in which latter- Fig. 1 is a side elevational view of a gas engine equipped with the improved starter mechanism.

Fig. 2 is a top plan view of the mechanism of Fi 1.

Fig. 3 is a detail top plan view of the gas engine cylinder showing the fuel feed mechanism.

Fig. 4 is a longitudinal sectional view taken along the line IVIV of Fig. 3.

Fig. 5 is a transverse sectional view taken along the line VV of Fig. 3.

Fig. 6 is a longitudinal sectional view through the air compressor cylinder at the compressed air inlet and taken along the line VI-VI of Fig. 3.

Fig. '7 is a transverse sectional view taken along the line VII--VII of Fig. 4.

Fig. 8 is a longitudinal sectional view through the air compressor.

Fig. 9 is a side elevational view of the crosshead of the air compressor.

Fig. 10 is a side elevational view of the crosshead with parts in section along the line X-X of Fig. 9.

Fig. 11 is a longitudinal sectional view of the automatic pressure responsive actuator with its supporting bracket shown in side elevation, and

Fig. 12 is a longitudinal sectional view of the compressor cylinder relief valve.

Referring particularly to the drawings, a gas engine is shown including a body portion 1 mounted upon a base 2 and provided with a cylinder 3. A piston head 5 is reciprocably mounted in the cylinder and is connected to a piston rod 6. Fuel such as natural gas is introduced into the fuel chamber (Fig. 5) '7 through a feed line 8 and index stop valve 9. Fuel air is admitted to the fuel chamber through an inlet 10. Suitable fuel firing apparatus, not shown, is connected to the cylinder 3 at 14. The fuel passes into the cylinder from the fuel chamber '7 through inlet port holes 15 and 16. The products of combustion are withdrawn from the cylinder through exhaust port holes 16' (see Fig. '7). The piston 6 is connected to a crosshead 20 which in turn actuates fly wheels 21 through a link 22.

The starter mechanism includes an air compressor 25 which is actuated by the gas engine to compress air which is conducted through a improvements in line 26 and 27 to a reservoir or air storage tank 28 where it is stored under pressure. The compressed air is utilized to start the engine by operating a valve 30 in line 27 to admit the air under pressure through an inlet 31 into the cylinder 4 against the head of the piston. The fly wheels have first been rolled over until the crank of the engine is approximately 15 or 20 past back center. The fuel gas has been turned on at the index stop 9. When the piston has been forced to the end of its stroke the compressed air stop cook 30 is closed quickly thereby permitting the piston to return on the compression stroke. The compressed air stop cook 30 is then opened and closed as often as necessary until the fuel has ignited and the engine is in operation. v

The air compressor includes a jacket 32 which is supported upon the gas engine by means of brackets 34 (see Fig. l). A cylinder 34a (see Fig. 8) is partially disposed within the jacket in spaced relation to the housing jacket providing a water chamber 34b. A piston is mounted for reciprocation within the cylinder and includes a piston head 35 having gaskets 36 of suitable flexible material for engaging the walls of the cylinder. A piston rod 37 is attached to the piston head 35. The intake air to the compressor enters the cylinder through an inlet 38 and passes through an opening 39 in the piston rod 37 through an opening 40 in, the head and past a ball check 41 within the piston head which acts as an inlet valve. A ball check 42 in an outlet passageway 43 of the cylinder acts as a discharge valve for the compressor. A line 26 previously described communicates with the discharge passageway 43. A check valve 44 is provided in the line 26.

The piston rod 3'7 of the air compressor is actuated by the crosshead of the engine by the following arrangement of parts. An arm is secured to the crosshead 20 of the engine. The arm 50 is provided with an opening 51 which is adapted to receive the end of the piston rod 3'7. The piston rod 37 is provided with an annular groove 52 which is adapted to be engaged by a latch key 53 carried by the arm 50. Reciprocation of the crosshead of the engine thereby effects corresponding reciprocation of the compressor piston. The latch key 53 is normally maintained in withdrawn position from the groove 52 of the piston rod by means of a helical spring 54 which is secured to a plate 55 affixed to the arm 50. The latch key is held in engagement with the groove 52 of the piston rod by means of a trip pin 56 having a lateral projection 57 which is mounted for longitudinal movement transversely of the arm 50. A helical spring 58 within the arm 50 maintains the latch key in a locked position to hold pressure on the lines 26 and 27 and the storage tank 28.

The air compressor is actuated until a pressure of air sufficient to start the engine is attained in the reservoir 28. Such a pressure'rnay be from approximately 50 pounds per square inch to in excess of 200 pounds per square inch. The pressure within the reservoir 28 is governed by a pressure responsive actuator 65, which is supported by a bracket 66 upon the body portion 1 of the engine and which communicates through a branch line 6'7 with the line 26 leading from the air compressor to the reservoir. The pressure responsive actuator contains a passageway 69 which is closed by a flexible diaphragm 70. A head 71 is forced against the diaphragm '70 by means of a helical spring '72. The pressure with which the helical spring bears against the head is governed by means of an adjustable nut 13. A stem 74 extends through the nut 73 and bears adjustably a nut 75. The nut '73 can be adjusted to regulate the pressure at which the nut '75 will be forced outwardly. The pressure responsive actuator is set to project the nut '75 outwardly when a desired air pressure such as 100 pounds per square inch or the like is attained in the reservoir 28. The nut 75 is then projected outwardly sufficiently far to engage the trip pin 56 when the air compressor piston rod is reciprocated to the intake end of its stroke' Engagement of the trip pin by the pressure responsive actuator forces the trip pin longitudinally to release the latch key 53 permitting the latch key to be withdrawn from thegroo've 52 of the air compressor piston rod and prevent further actuation of the compressor.

Upon the reverse stroke of the gas engine a cylinder relief valve is opened allowing the air ahead or the compressor piston to escape and permitting the compressor piston to remain at the end of the compression stroke. The cylinder relief valve comprises a body portion which is connected by means of a line 81 with theline 26 between the safety valve 44 and the air compressor cylinder. A spring pressed valve 82 normally prevents escape of the compressed air through ports 83. A valve stem 84 projects from the body portion in position to be struck by the trip pin 56 whereby the valve 82 is opened and the air ahead of the compressor piston escapes.

The invention has been described as applied to starting a gas engine but it will be understood that it is applicable to any form of internal combustion engine.

Various changes may be made within the scope of the appended claims in which it is desired to all novelty inherent in the invention as broadly as the prior art permits.

I claim:

1. In combination, an engine, a compressor having a piston rod, an arm operatively connecting the engine piston and the piston rod, a

the compressor piston rod and the arm and adapted to be engaged by the extensible portion to disconnect the compressor and gas engine, when a predetermined pressure in the reservoir is attained.

2. In combination, an engine, a cross head associated with the engine, a gas compressor having a piston rod, an arm operatively connecting the cross head and piston rod, a reservoir, a line connecting the compressor and reservoir, a pressure responsive actuator in the line and having an extensible portion, and a trip pin carried by the arm detachably connecting with the piston rod and arm and adapted to be engaged by the extensible portion to disconnect the compressor and cross head when a predetermined pressure in the reservoir is attained.

3. Apparatus according to claim 1 including a rod controlling an escape valve on the compressor to release gas pressure in the compressor and actuated by the trip pin.

4. In combination, an engine, a gas compressor, means operatively connecting the engine to the compressona reservoir connected to receive the compressed gas, means for disconnecting the engine from the compressor atone end of the stroke of the compressor when a predetermined pressure is attained in the reservoir, and means for releasing the gas pressure ahead of the compressor at the opposite end of the stroke of the'compressor.

5. In combination, an'engine, a gas compressor, a latched arm operatively connecting the engine to the compressor, a reservoir connected to receive the compressed gas, and a pressure responsive actuator communicating'with-the reservoir having a portion adapted to be projected by the compressed gas into position to disengage the latch at one end of the stroke of the compressor when a predetermined pressure is attained in the reservoir, whereby the engine is released from the compressor.

6. In combination, an engine, a gas compressor, a latched arm operatively connecting the engine with the compressor, a reservoir connected to receive the compressed gas, a pressure responsive actuator communicating with the reservoir hav ing a portion adapted to be projected by the compressed gas into position to disengage the latch at one end of the stroke of the compressor when a predetermined pressure is attained in there-servoir, whereby the engine is released from the compressor, and means for releasing the gas pressure ahead of the compressor, at the opposite end of the stroke of the compressor.

'1. In combination, an engine, a gas compressor, a latched arm operatively connecting the engine to the compressor, a reservoir connected to receive the compressed gas, a pressure responsive actuator communicating with the reservoir having a portion adapted to be projected by the compressed gas into position to move the machine laterally to disengage the latch at one end of the stroke of the compressor'when a predetermined pressure is attained in the reservoir, whereby the engine is released from the compressor, and an'escape valve communicating with the opposite end of the compressor operated to be opened by the moved latch at the opposite end of the stroke of the compressor.

' WILLIAM OTHO BICKERSTAFF. 

